generate XML from a dynamic dataset - asp.net

Question

I have an ASP.net application in c# where I have a dataset which I can transfer to xml by using the following simple codeblock:
string result;
using (StringWriter sw = new StringWriter())
{
ds.WriteXml(sw);
result = sw.ToString();
}
Which generates an xml block like the following:
<NewDataSet>
<ImageInfo>
<ImageID>1</ImageID>
<ImageName>untitled.bmp</ImageName>
<ImagePath>Some Path</ImagePath>
<Width>800</Width>
<Height>190</Height>
<TileSize>256</TileSize>
<Overlap>1</Overlap>
<MimeType>image/jpeg</MimeType>
<Scale />
</ImageInfo>
</NewDataSet>
This is obviously an example of one row, there are multiple rows in the dataset. Now, I dont know how to format a XML block dynamically.
Can anyone point me to some good tutorials on this?
I want the XML to be formatted like the following
<data>
<Columns>
<Column Name= "ImageID"/>
<Column Name= "ImageName"/>
<Column Name= "ImagePath"/>
<Column Name= "Width"/>
<Column Name= "Height"/>
<Column Name= "TileSize"/>
<Column Name= "Overlap"/>
<Column Name= "MimeType"/>
<Column Name= "Scale"/>
</Columns>
<Rows>
<Row>
<Cell>1</Cell>
<Cell>untitled.bmp</Cell>
<Cell>Some Path</Cell>
<Cell>800</Cell>
<Cell>190</Cell>
<Cell>256</Cell>
<Cell>1</Cell>
<Cell>image/jpeg</Cell>
<Cell></Cell>
</Row>
<Row>
.
.
.
</Row>
</Rows>
</data>
Can anyone guide me how to do this?
In my application, I wont be knowing the structure of the dataset beforehand. i.e. there can be a resulting dataset where I have more columns than the ones described in the example. How should I go about this? Any help would be much appreciated.

Answer 1

Try using a DataTable and then convert that DataTable to an XML stream or a file.
DataTable myDataTable = myDataSet.Tables[0];
myDataTable.WriteXml(..);
You will find whole bunch of overloads like TextWriter, Stream. Finally you need to modify that xml to add the nodes besides that DataTable.

Answer 2

This can be a work around. The code standard can be better but for now you can use the following:
XmlDocument doc = new XmlDocument();
XmlDocument Outputdoc = new XmlDocument();
doc.LoadXml("<NewDataSet> <ImageInfo> <ImageID>1</ImageID> <ImageName>untitled.bmp</ImageName> <ImagePath>Some Path</ImagePath> <Width>800</Width> <Height>190</Height> <TileSize>256</TileSize> <Overlap>1</Overlap> <MimeType>image/jpeg</MimeType> <Scale /> <ImageID>1</ImageID> <ImageName>untitled.bmp</ImageName> <ImagePath>Some Path</ImagePath> <Width>800</Width> <Height>190</Height> <TileSize>256</TileSize> <Overlap>1</Overlap> <MimeType>image/jpeg</MimeType> <Scale /></ImageInfo> </NewDataSet> ");
XmlNode node = doc.SelectSingleNode("/NewDataSet/ImageInfo");
XmlNodeList nodes = node.ChildNodes;
XmlDocument newdoc = null;
StringBuilder sb = new StringBuilder("<data><Columns>");
string lastNode=string.Empty;
string firstNode = string.Empty;
foreach (XmlNode n in node.ChildNodes)
{
if(n.Name.Equals(firstNode))
break;
if (string.IsNullOrEmpty(firstNode))
firstNode = n.Name;
newdoc = new XmlDocument();
XmlNode newNode = newdoc.CreateElement("Column");
XmlAttribute newAttribute = newdoc.CreateAttribute("Name");
newAttribute.Value = n.Name;
newNode.Attributes.Append(newAttribute);
newdoc.AppendChild(newNode);
sb.Append(newdoc.InnerXml);
lastNode=n.Name;
}
sb.Append("</Columns><Rows><Row>");
foreach (XmlNode xnode in node.ChildNodes)
{
XmlDocument newdoc1 = new XmlDocument();
XmlNode newNode = newdoc1.CreateElement("Cell");
newNode.InnerText = xnode.InnerText;
newdoc1.AppendChild(newNode);
sb.Append(newdoc1.InnerXml);
if (xnode.Name.Equals(lastNode))
sb.Append("</Row>");
}
sb.Append("</Rows></data>");
This is a very quick way to accomplish your task. You are free to standarize the code. Now look at the output which looks same as you need:
<data>
<Columns>
<Column Name="ImageID" />
<Column Name="ImageName" />
<Column Name="ImagePath" />
<Column Name="Width" />
<Column Name="Height" />
<Column Name="TileSize" />
<Column Name="Overlap" />
<Column Name="MimeType" />
<Column Name="Scale" />
</Columns>
<Rows>
<Row>
<Cell>1</Cell>
<Cell>untitled.bmp</Cell>
<Cell>SomePath</Cell>
<Cell>800</Cell>
<Cell>190</Cell>
<Cell>256</Cell>
<Cell>1</Cell>
<Cell>image/jpeg</Cell>
<Cell></Cell>
</Row>
<Cell>1</Cell>
<Cell>untitled.bmp</Cell>
<Cell>Some Path</Cell>
<Cell>800</Cell>
<Cell>190</Cell>
<Cell>256</Cell>
<Cell>1</Cell>
<Cell>image/jpeg</Cell>
<Cell></Cell>
</Row>
</Rows>
</data>
Note: I have used the same data collection to make two rows of data.